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                道路改建                </h1>
                <p>时间限制：10s&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;  空间限制：128MB</p>			</div>
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                                <h3>题目描述</h3><p><div>人称不死将军的林登&bull;万，与他的兄弟林登&bull;图两人的足迹踏遍了地球的每一寸土地。他们曾将战火燃遍了世界。即使是lifei888这样的强悍人物也从来没有将他彻底击败。</div>
<div>这一次，林登&bull;万在N个城市做好了暴动的策划。然而，在起事的前一天，将军得知计划已经泄漏，决定更改计划，集中力量掌握一部分城市。</div>
<div>具体来说，有M条单向边连接着这N座城市。对于两座城市A,B，如果它们能够通过单向边直接或间接的互相到达，那么就林登&bull;万可以同时控制A,B两座城市而不至于分散力量，反之则会被lifei888各个击破。</div>
<div>为了扩大成果，将军还组织了人手改建道路。这些人可以在起事前将其中一条有向边改变成双向边（注意只能改建其中一条单向边，另外M-1条单向边保持不变）,现在，将军想要知道他通过改建其中一条单向边最多能控制几座城市，以及被改建的这一条单向边有多少种选择方案。</div>
<p></p></p><hr/><h3>输入格式</h3><p><div>第一行为两个正整数N,M。</div>
<div>接下来M行每行两个范围在1~N内的正整数x,y，表示有一条从x到y的单向边。</div>
<div>输入保证任意两点的任意方向最多只有一条边直接相连。</div>
<p></p></p><hr/><h3>输出格式</h3><p><div>输出共三行。</div>
<div>第一行一个正整数，将军最多能控制的城市数量。</div>
<div>第二行一个正整数L，表示有L种改建方案使得将军能控制最多的城市。</div>
<div>第三行L个按递增顺序给出的正整数ki，表示改建输入中的第ki条有向边能使将军能控制最多的城市。</div>
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<p></p></p><hr/><h3>样例输入</h3><pre>5 4
1 2
2 3
1 3
4 1
</pre><hr/><h3>样例输出</h3><pre>3
1
3
</pre><hr/><h3>提示</h3><p><p class="MsoNormal"><span style="font-family:宋体;mso-ascii-font-family:&quot;Times New Roman&quot;;
mso-hansi-font-family:&quot;Times New Roman&quot;">对于</span><span lang="EN-US">100%</span><span style="font-family:宋体;mso-ascii-font-family:&quot;Times New Roman&quot;;mso-hansi-font-family:
&quot;Times New Roman&quot;">的数据，</span><span lang="EN-US">N&lt;=<st1:chmetcnv unitname="m" sourcevalue="2000" hasspace="True" negative="False" numbertype="1" tcsc="0" w:st="on">2000 M</st1:chmetcnv>&lt;=N*N</span></p>
<p></p></p><hr/><h3>题目来源</h3><p>没有写明来源</p>
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